1. Field of the Invention
The present invention relates to zippers comprising interlocking flexible closure strips extruded from synthetic polymeric resin materials. More specifically, it is a zipper of this variety intended for use in closing out the covers of automobile seat backs in a manner that is unseen by, or hidden from, the casual observer. The flexible closure strips include webs to which seat cover material may be connected, sewn or attached in a conventional manner.
2. Description of the Prior Art
In the manufacture of seats for automobiles, trucks and other motor vehicles, a seat back, which may include a rigid frame having at least some resilient padding material attached thereto, is often covered from the top with a pre-manufactured, sacklike seat cover. The seat back must then be "closed out" at the bottom thereof by securing the sides of the seat cover opening to one another. Ordinarily, the closure, which runs along the bottom of the seat back, is hidden from view, as, in a fully assembled seat, it resides in the tight space between the bottom of the seat back and the substantially horizontal portion of the seat forming the seating surface.
In the past, automobile seat covers, including seat back covers have been closed out using conventional zippers comprising interlocking teeth and a pull tab. While strong and reliable, and capable of being closed in an unsupported situation (that is, without requiring a firm backing surface), conventional zippers are an unnecessarily expensive means for closing out a seat back cover which is never intended to be reopened. In addition, they may be very difficult to hide completely from view.
Auto manufacturers have long searched for alternatives to conventional zippers for use in closing out seat covers, including seat back covers. So-called J-bar and arrow fasteners provide a good alternative, but carry the disadvantage of requiring a support surface against which they may be fastened. This hampers their use in auto seating, as much of the interior of an auto seat is either empty, or filled with quite resilient foam.
Manufacturers have attempted to circumvent this disadvantage by closing out auto seat backs having J-bar fasteners in an apparatus having a rigid plate member which is inserted into one of the two halves of the fastener to provide the required rigid support and to immobilize that half of the fastener. The rigid plate also stretches that side of the auto seat back cover across the bottom of the seat back. The operator of the apparatus then manually stretches the other side of the opening of the seat back cover across the bottom of the seat so that the other half of the J-bar fastener attached thereto may be engaged with the immobilized one.
From a technical point of view, this method of closing out auto seat backs has proven to be quite satisfactory. However, the repetitive motion required by the operator who must manually close out hundreds of seat backs in a typical work shift with a turning wrist action has been the source of many work-related injuries, including those of the repetitive motion type producing what has come to be known as carpal tunnel syndrome.
The present invention provides a solution to this problem of the prior art.